A Clinical Epidemiological Study On Chronic Urticaria

ObjectiveChronic urticaria(CU) is one of the most common and frequently occurring diseases ofdermatology. Increased distention and permeability of small vessels of skin and mucousmembrane lead to local edema. Causes of chronic urticaria are not clear, possibly related tofoods, drug, physical stimuli, infection, mosquito bite, mental factors, working pressure,and so on. It mainly presented with wheal and/or angioedema. Among all of the clinicaltypes, chronic spontaneous urticaria(CSU) is the most common pattern. Chronic urticariapatients mainly received symptomatic treatment with high recurrence rate so that the qualityof life was affected severely. As yet, we should pay close attention to chronic urticaria.Epidemiological feature of CU is a basis for correct clinical therapy and prevention.There are a lot of epidemiological surveys of CU in abroad but a little in China, especiallyanalysis about causes of CU. Therefore, a survey about CU was conducted from January toSeptember2010in our hospitals about analyzing the clinical epidemiological feature,accessing quality of life, discussing drug or other allergy factors which lead to CU in ourdaily life via in vivo test and in vitro test. Through analyzing clinic data of subjects and testresults, it is helpful that the investigations of CU clinical epidemiological characteristicsand influence of quality of life as well as the cause of CU guideline the managementstrategies.MethodsSubjects: Subjects were diagnosed with chronic urticaria in Southwest Hospital ofThird Military Medical University in Chongqing from January to September2010.Methods: According to WAO guideline, we designed epidemiological survey question-naires of urticaria.535subjects were diagnosed CU by dermatologists and required tofulfill the self-report questionnaires. The basic information of the subjects included age ofprimary occurence, illness course, causes, classification, pruritus degree, frequency, combin -ation of angioedema, family history, autologous serum skim test(ASST), previoustherapies, and so on.421subjects finished questionnaires of dermatology life quality index(DLQI), and doctors and subjects access the degree of disease respectively.16subjects withthe unknown cause of CU and6health controls received patch test, lymphocyte activationtest (LAT) and cytotoxicity-based assays. EpiData and SPSS13.0were utilized for statisticalanalysis, including nonparametric statistics, delineation, chi-square test, t test, Pearsonrelative test, Cronbach’sα, factor and validity test, and so on.Main results1.An epidemiological signature Totally, there are535subjects utility epidemiologicalquestionnaires,331were female and204were male with a mean age of (34.4±14.0)years,covering from1to82old. The average age of subjects with CU at first episode was(30.6±14.8) years, ranging from1to81. It peaked in patients aging from20to40years.There are no notable relation among subjects in educational background, revenue andposition. Family history with hypersensitivity disease includes52urticaria,6asthma,6contact dermatitis,6allergic rhinitis. The self-reported eliciting factors of urticaria were asfollows: unknown factors263(49.2%), physical stimuli94(17.6%), others54(10.0%),mental factor39(7.3%), foods29(5.4%), mosquito bite24(4.5%), drugs23(4.3%)andworking pressure9(1.7%) in order.Among various clinical types, chronic spontaneous urticaria(CSU) was the mostcommon type, which accounted for294(55.0%), followed by dermographic urticaria factitia120(22.4%), while the rarest types were solar urticaria，contact urticaria and aquagenicurticaria. No delayed pressure urticaria, exercise induced urticaria and vibratory urticaria werefound.69cases of dermographic urticaria factitia followed different types of CU. Among them,there were55CSU,5heat contact urticaria,3cold contact urticaria,1cholinergic urticaria,1solarurticaria. Angioedema in CU accounted for105(19.6%) with female70(21.1%) and male35(17.2%).Among them, there were76(25.9%) CSU,13(10.9%) dermographic urticaria factitia,10(14.5%)co-exist dermographic urticaria factitia and other kinds of urticaria,4(21.1%) cold contacturticaria,1(7.1%) cholinergic urticaria,1(6.3%) heat contact urticaria with angioedema. Thelasting time of wheal was longer when angioedema followed CU(P<0.05), there were nonotable differences of other clinical feature whether or not angioedema (P＞0.05).Totally,254subjects participated in autologous serum skim test(ASST) with126 (49.6%) positive ASST, including95(55.9%) female and31(36.9%) male in it. All kinds ofCU with positive ASST includes:89(63.6%) CSU，2(28.6%)cold contact urticaria，15(23.1%) dermographic urticaria factitia,4(80.0%) heat contact urticaria,2(100.0%) cholinergicurticaria,1(100.0%) aquagenic urticaria,13(40.6%) others. We found that between positiveand negative ASST: female of CU with positive ASST higher than male, positive ASSTcases took place more angioedema and longer lasting time of wheal than negative ASST(P<0.05).The average course of CU with negative ASST was (45.8±62.1)months，and positive ASST was(61.2±99.6) months(P<0.05). The average age of positive ASST with CU at first episode was(28.4±15.0) years from1to64, the average age of negative ASST with CU at first episode was(31.5±14.4)years from2to75. There were no differences between ASST and first age(Z=-1.54，P＞0.05).2. Accessing quality of life421patients were asked to complete DLQI, with158males and263females from16to68years old, and a mean age was (35.52±11.57) years.The average course of CU of female was (56.55±91.28) months and male was (38.42±56.84) months(t=2.510，P<0.01). The DLQI score, which varied from1to30with anaverage of9.30士6.05. In "daily life", females more influence than male[male(1.39士1.38)，female(1.84士1.54)，t=3.018，P<0.01]. CU with angioedema were influenced morethan only wheal(P<0.05). The impact of CU was observed, mainly on the "symptoms andfeeling"(46.3%), followed by "work and study", the least on "interpersonal relationship"(17.7%). Excluding occupation or lasting time with wheal or sleeping, varity factors werecorrelated to DLQI. For example, years of age, marriage, mental status, and so on.The result of the survey in which dermatologists and subjects access disease respective-ly were reflected high reliability and had direct correlation with DLQI. Reliability analysisshowed that F=282.86(P<0.01), In Hotelling’s T-Squared test, F=230.84(P<0.01),Cronbach’sα=0.8773. There were no excluding items. Correlation coefficient ranges from0.392to0.698in items(P<0.01). DLQI had high reliability and validity.3.Etiological survey There were16subjects with unclear cause of CU,9were femaleand7were male, with a mean age was35.81士13.50years. The average course of CU was67.19士86.35months. The control group includes6healths subjects with a mean age of33.00士9.84years. In the path test, the results showed that except one niekel sulfate(number5) and sulfanilamide (number9) respective were positive, others were negative. In CU, CD69(PE staining) expresses0.3%～19.0%, CD107a(FITC staining) expresses0.6%～8.8%, both expresses0.1%～4.5%with CD3(Percp-cy5,5staining). In positivecontrol(PMA+Iono), CD69expresses21.8%～37.75%, CD107a expresses7.8%～16.7%，both expresses2.5%～19.4%. In the health control group, CD69expresses1.1%～2.1%,CD107a expresses0.6%～3.6%, both expresses0.3%～1.9%. Except others and healthcontrol, in sulfanilamide(number9), niekel sulfate(number5) and acetaminophen(number13), PBMC of CD3with surface molecule CD69and cytotoxicity moleculeCD107a as wellas both of them expresses up-regulation. CD69expresses up-regulation more than CD107ain average.Main conclusions：1.CU can be found in any ages. The prevalence of CU peaked in patients aging from20to40years. It oftten occurs among females. The mean age was (34.4±14.0) year and theaverage age at first was (30.6±14.8) years. Subjects do not have notable relation ineducational background, revenue and position. The self-reported eliciting factors of CUwere unknown factors around to1/2, and a litter relate to physical stimuli, mental factor,foods, mosquito bite, drugs, working pressure, and so on. Urticaria was the most commonin direct relative with hypersensitivity disease in family history.2.In non-acute urticaria, CSU was the most common type. Dermographic urticariafactitia were the most common in physical urticaria which can occur dependently or with allkinds of urticaria.3.The ratio of angioedema in CU accounted for1/5, and25.9%in CSU. Females seemto have higher prevalence rate than males. Lasting time of wheal of angioedema followedCU was longer. There were ASST positive rate: CU49.6%, CSU63.6%. All kinds ofurticaria can positive ASST, it was refluence that autoimmune not only in CSU but alsocorrelate to all kinds of urticaria. Positive ASST contrast to negative taking place moreangioedema and longer lasting time of wheal or average course.4.The average DLQI score was (9.30士6.05). CU influence quality of life withmoderate degree. In "daily life", females more influence than male. More influence CUwith angioedema than only wheal. The impact of CU was observed, mainly on the"symptoms and feeling"(46.3%), the least on"interpersonal relationship"(17.7%). Excludingoccupation or lasting time with wheal or sleeping, varity factors were correlated to DLQI. For example, years of age, marriage, mental status, and so on.5.Surface molecule(CD69) in LAT and cytotoxicity molecule(CD107a) in cytotoxicity-based assays can analysis etiological of CU. CD69, CD107a and both of them expressesup-regulation. It is may be imply that subjects were correlated with drugs. CD69averageexpresses up-regulation more than CD107a suggest that LAT may be more sensitive thancytotoxicity-based assays. There were no certain correlation between CU with unclearcause and drugs or other allergy factors.As for CU with unknown causes, especially when it is lack of methods of specificity,skin path test, LAT, cytotoxicity-based assays can be used as an etiological screen methodas well as an aid.The results of skin path test and in vitro test provide helpful reference inthe field of etiology.